{"id":619,"date":"2020-08-20T17:14:37","date_gmt":"2020-08-20T09:14:37","guid":{"rendered":"http:\/\/www.wangkaixuan.tech\/?p=619"},"modified":"2020-08-20T17:14:37","modified_gmt":"2020-08-20T09:14:37","slug":"libevent%e4%ba%8b%e4%bb%b6%e5%be%aa%e7%8e%af%e7%9a%84%e5%87%a0%e7%a7%8d%e6%96%b9%e5%bc%8f","status":"publish","type":"post","link":"http:\/\/www.wangkaixuan.tech\/?p=619","title":{"rendered":"libevent\u4e8b\u4ef6\u5faa\u73af\u7684\u51e0\u79cd\u65b9\u5f0f"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">1.\u6700\u7b80\u5355\u7684\u65b9\u5f0f<\/h2>\n\n\n\n<p>\u6700\u7b80\u5355\u7684\u4f7f\u7528\u65b9\u5f0f\u662f\u8c03\u7528event_base_dispatch\uff0c\u58f0\u660e\u5982\u4e0b\uff1a<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"648\" height=\"272\" src=\"http:\/\/www.wangkaixuan.tech\/wp-content\/uploads\/2020\/08\/image-82.png\" alt=\"\" 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class=\"wp-block-heading\">a) flags\u6307\u5b9a\u4e3a0<\/h3>\n\n\n\n<p>\u5373\u76f8\u5f53\u4e8e\u524d\u9762\u7684\u7b80\u5355\u7528\u6cd5\u3002\u8fd9\u79cd\u60c5\u51b5\u4e0bevent_loop\u4f1a\u963b\u585e\uff0c\u56e0\u6b64\u53ea\u9700\u8981\u8c03\u7528\u4e00\u6b21\u3002\u4f46\u95ee\u9898\u662f<strong>\u5373\u4f7f\u8fd9120\u5b57\u8282\u5df2\u7ecf\u6536\u5b8c\u4e86\uff0cevent_loop\u4e5f\u4e0d\u4f1a\u9000\u51fa<\/strong>\uff0c\u8fd9\u4e0d\u662f\u6211\u4eec\u60f3\u8981\u7684\u6548\u679c\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">b) flags\u6307\u5b9a\u4e3aEVLOOP_ONCE<\/h3>\n\n\n\n<p>\u8be5flag\u7684\u542b\u4e49\u662f\uff0c\u6bcf\u6b21\u5faa\u73af<strong>\u53ea\u5904\u7406\u4f18\u5148\u7ea7\u6700\u9ad8\u7684\u4e00\u4e2a\u4e8b\u4ef6<\/strong>\u3002<\/p>\n\n\n\n<p>\u5728\u4e0a\u9762\u7684\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u9700\u8981\u8fd0\u884c\u4e24\u6b21event_loop\uff0c\u7b2c\u4e00\u6b21\u54cd\u5e94\u53ef\u8bfb\u4e8b\u4ef6\u653640\u5b57\u8282\u7684\u6570\u636e\uff0c\u7b2c\u4e8c\u6b21\u54cd\u5e94\u53ef\u8bfb\u4e8b\u4ef6\u6536\u5269\u4f59\u768480\u5b57\u8282\u7684\u6570\u636e\u3002<\/p>\n\n\n\n<p>\u867d\u7136\u8fd9\u6b21event_loop\u4e0d\u4f1a\u963b\u585e\u4e86\uff0c\u4f46\u662f<strong>event_loop\u7684\u6548\u7387\u53c8\u592a\u4f4e\u4e86<\/strong>\uff0c\u4e5f\u4e0d\u662f\u6211\u4eec\u60f3\u8981\u7684\u6548\u679c\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">c) flags\u6307\u5b9a\u4e3aEVLOOP_NONBLOCK<\/h3>\n\n\n\n<p>\u8be5flags\u7684\u542b\u4e49\u662f\uff0c\u6bcf\u6b21event_loop\u4f1a\u5faa\u73af\u5904\u7406\u5b8c\u6240\u6709\u4e8b\u4ef6\uff0c\u76f4\u5230\u6ca1\u6709\u65b0\u7684\u5f85\u5904\u7406\u4e8b\u4ef6\u4e3a\u6b62\u3002<\/p>\n\n\n\n<p>\u5728\u4e0a\u9762\u7684\u4f8b\u5b50\u4e2d\uff0cevent_loop\u4f1a\u5728\u5185\u90e8\u8fd0\u884c\u4e24\u8f6e\u4e8b\u4ef6\u5faa\u73af\uff0c\u7b2c\u4e00\u8f6e\u54cd\u5e94\u53ef\u8bfb\u4e8b\u4ef6\u6536\u53d640\u5b57\u8282\u7684\u6570\u636e\uff1b\u7b2c\u4e8c\u8f6e\u6536\u53d6\u5269\u4f5980\u5b57\u8282\u7684\u6570\u636e\u3002\u4e24\u8f6e\u4e8b\u4ef6\u5faa\u73af\u7ed3\u675f\u540e\uff0cevent_loop\u9000\u51fa\u3002<\/p>\n\n\n\n<p>\u8fd9\u6b63\u662f\u6211\u4eec\u60f3\u8981\u7684\u6548\u679c\uff0c\u5373\u4e0d\u4f1a\u963b\u585e\u5f53\u524d\u7ebf\u7a0b\uff0cevent_loop\u7684\u6548\u7387\u53c8\u9ad8\u3002<\/p>\n\n\n\n<p>\u4f46\u662f\u8fd9\u79cd\u884c\u4e3a\u6709\u4e00\u4e2a\u95ee\u9898\uff0c\u5373\u5982\u679c\u8fde\u63a5\u5f88\u7e41\u5fd9\uff0c\u4e00\u76f4\u6709\u6570\u636e\u4ece\u7f51\u7edc\u4e0a\u8fc7\u6765\uff0c\u90a3\u4e48event_loop\u4f1a\u4e00\u76f4\u65e0\u6cd5\u9000\u51fa\u3002\u56e0\u6b64<strong>\u53ea\u9002\u7528\u4e8e\u4e8b\u4ef6\u5faa\u73af\u4e0d\u592a\u7e41\u5fd9\u7684\u573a\u666f<\/strong>\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">d) flags\u6307\u5b9a\u4e3aEVLOOP_NO_EXIT_ON_EMPTY<\/h3>\n\n\n\n<p>\u8be5flags\u6bd4event_base_dispatch\u7684\u884c\u4e3a\u8fd8\u8981\u6781\u7aef\u3002event_base_dispatch\u5728\u6ca1\u6709\u4efb\u4f55\u6ce8\u518c\u4e8b\u4ef6\u7684\u65f6\u5019\u4f1a\u9000\u51fa\uff0c\u800c\u6307\u5b9a\u4e86\u8be5\u6807\u8bb0\u7684event_base_loop\u4e0d\u4f1a\u3002<\/p>\n\n\n\n<p>\u4e24\u8005\u76f8\u540c\u7684\u4e00\u70b9\u662f\uff0c\u7528\u6237\u4e3b\u52a8\u8c03\u7528event_base_loopbreak\u6216event_base_loopexit\u662f\u53ef\u4ee5\u7ed3\u675f\u4e8b\u4ef6\u5faa\u73af\u7684\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">3.\u603b\u7ed3<\/h2>\n\n\n\n<p>\u6bcf\u79cd\u73a9\u6cd5\u9002\u7528\u4e8e\u4e0d\u540c\u7684\u573a\u666f\uff0clibevent\u7684\u8bbe\u8ba1\u8005\u90fd\u63d0\u524d\u60f3\u5230\u4e86\uff0c\u5927\u5bb6\u53ef\u4ee5\u6839\u636e\u4e0d\u540c\u7684\u5e94\u7528\u573a\u666f\u7075\u6d3b\u9009\u7528\u3002<\/p>\n\n\n\n<p>\u5982\u679c\u4f60\u542c\u4e0d\u61c2\u6211\u4e0a\u9762\u8bf4\u7684\u4ec0\u4e48\uff0c\u8bc1\u660e\u4f60\u5bf9\u7f51\u7edc\u7f16\u7a0b\u8fd8\u4e0d\u719f\u6089\uff0c\u5c24\u5176\u662f\u53cd\u5e94\u5668\u6a21\u5f0f\u4e0d\u592a\u719f\u6089\uff0c\u8fd9\u91cc\u63a8\u8350\u4e00\u672c\u4e66\u300aLinux\u591a\u7ebf\u7a0b\u670d\u52a1\u7aef\u7f16\u7a0b-\u4f7f\u7528muduo\u7f51\u7edc\u5e93\u300b\u3002\u6211\u5c31\u662f\u4ece\u8fd9\u672c\u4e66\u5f00\u59cb\u5165\u95e8\u7f51\u7edc\u7f16\u7a0b\u7684\u3002<\/p>\n\n\n\n<p>\u53e6\u5916\u591a\u8bf4\u4e00\u70b9\uff0c\u6211\u672c\u4eba\u5728\u5f00\u53d1\u8fc7\u7a0b\u4e2d\u6df1\u5ea6\u4f7f\u7528\u8fc7\u4e24\u4e2a\u7f51\u7edc\u5e93\uff0c\u4e00\u4e2a\u662fACE\uff0c\u4e00\u4e2a\u662flibevent\uff0c\u8fd8\u57fa\u4e8elibevent\u5c01\u88c5\u4e86\u4e00\u4e2a\u529f\u80fd\u5b8c\u5907\u3001\u4f7f\u7528\u8d77\u6765\u66f4\u7b80\u5355\u7684\u7f51\u7edc\u5e93\uff0c\u8fd8\u505a\u8fc7\u51e0\u4e2a\u5de5\u4e1a\u7ea7\u7684\u4ee5\u7f51\u7edc\u901a\u4fe1\u4e3a\u6838\u5fc3\u529f\u80fd\u7684\u7cfb\u7edf\uff0c\u56e0\u6b64\u5728\u7f51\u7edc\u7f16\u7a0b\u65b9\u9762\u8fd8\u662f\u6709\u53d1\u8a00\u6743\u7684\u3002<\/p>\n\n\n\n<p>\u542c\u6211\u4e00\u53e5\u529d\uff0c<strong>\u5343\u4e07\u522b\u78b0ACE<\/strong>\u3002\u8981\u7528\u597d\u8fd9\u4e2a\u5e93\uff0c\u9700\u8981\u76f8\u5f53\u7684\u529f\u529b\u624d\u884c\u3002\u5bf9\u529f\u529b\u7684\u8981\u6c42\u4e0d\u4e9a\u4e8e\u80fd\u91cd\u65b0\u5199\u4e00\u4e2a\u7b80\u5355\u7684\u7f51\u7edc\u5e93\u3002<\/p>\n\n\n\n<p>\u53e6\u5916\u4e00\u4e2a\u539f\u56e0\u662f\uff0c\u8fd9\u4e2a\u5e93\u81f3\u4eca\u8fd8\u6709\u4e00\u4e2a\u6211\u53d1\u73b0\u7684\u672a\u4fee\u590d\u7684bug\uff0c\u6211\u4eec\u5728\u5b9e\u9645\u9879\u76ee\u4e2d\u91c7\u7528\u7ee7\u627f\u66ff\u6362\u5b9e\u73b0\u7684\u65b9\u5f0f\u89e3\u51b3\u4e86\u8fd9\u4e2a\u95ee\u9898\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>1.\u6700\u7b80\u5355\u7684\u65b9\u5f0f \u6700\u7b80\u5355\u7684\u4f7f\u7528\u65b9\u5f0f\u662f\u8c03\u7528event_base_dispatch\uff0c\u58f0\u660e\u5982\u4e0b\uff1a \u6ce8\u518c\u5b8c\u4e8b\u4ef6\u540e\uff0c\u8c03\u7528\u6b64\u51fd\u6570\uff0c\u5f53\u524d\u7ebf\u7a0b\u5373\u8fdb\u5165\u6b64\u51fd\u6570\u4e2d\u6267\u884c\u4e8b\u4ef6\u5faa\u73af\u3002\u9664\u975e\u7528&#8230;<\/p>\n<p class=\"read-more\"><a class=\"btn btn-default\" href=\"http:\/\/www.wangkaixuan.tech\/?p=619\"> Read More<span class=\"screen-reader-text\">  Read More<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[14],"tags":[],"class_list":["post-619","post","type-post","status-publish","format-standard","hentry","category-05-01-"],"_links":{"self":[{"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=\/wp\/v2\/posts\/619","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=619"}],"version-history":[{"count":0,"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=\/wp\/v2\/posts\/619\/revisions"}],"wp:attachment":[{"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=619"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=619"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.wangkaixuan.tech\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=619"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}